diff --git a/ecmascript/transforms/src/compat/es2015/block_scoping.rs b/ecmascript/transforms/src/compat/es2015/block_scoping.rs
index 22d0c49a4f15..afd7256a4db9 100644
--- a/ecmascript/transforms/src/compat/es2015/block_scoping.rs
+++ b/ecmascript/transforms/src/compat/es2015/block_scoping.rs
@@ -1440,9 +1440,54 @@ expect(foo()).toBe(false);
             )
         }
         ",
-        "
-        
-        "
+        r#"
+        var regeneratorRuntime = require("regenerator-runtime");
+        var _marked = regeneratorRuntime.mark(_foo);
+        function _foo() {
+            _foo = _asyncToGenerator(regeneratorRuntime.mark(function _callee() {
+                return regeneratorRuntime.wrap(function _callee$(_ctx) {
+                    while(1)switch(_ctx.prev = _ctx.next){
+                        case 0:
+                            _ctx.next = 2;
+                            return Promise.all([
+                                [
+                                    1
+                                ],
+                                [
+                                    2
+                                ],
+                                [
+                                    3
+                                ]
+                            ].map(_asyncToGenerator(regeneratorRuntime.mark(function _callee1(param) {
+                                var _param = _slicedToArray(param, 1), a = _param[0];
+                                return regeneratorRuntime.wrap(function _callee$1(_ctx1) {
+                                    while(1)switch(_ctx1.prev = _ctx1.next){
+                                        case 0:
+                                            return _ctx1.abrupt("return", Promise.resolve().then(function() {
+                                                return a * 2;
+                                            }));
+                                        case 1:
+                                        case "end":
+                                            return _ctx1.stop();
+                                    }
+                                }, _callee1);
+                            }))));
+                        case 2:
+                            _ctx.sent;
+                        case 3:
+                        case "end":
+                            return _ctx.stop();
+                    }
+                }, _callee);
+            }));
+            return _foo.apply(this, arguments);
+        }
+        function foo() {
+            return _foo.apply(this, arguments);
+        }
+
+        "#
     );
 
     test_exec!(